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Science China Earth Sciences 2008年第9期51卷 1297-1305页

作者： LI HaiOu XU XiWei JIANG Mei Institute of Geology China Earthquake AdministrationBeijing 100029China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

Teleseismic receiver functions and travel-time residuals along the north Hi-Climb broadband seismic array in the central-southern Qinghai-Tibet Plateau show that the lithosphere structures in the central and western Qinghai-Tibet Plateau are different. In the central Qinghai-Tibet Plateau, the Indian Plate is northward subducted beneath the Qiangtang block and arrives at the greatest depth beneath the central-southern Qiangtang block. The delaminated Indian lithospheric slab remains beneath the central Lhasa block to a depth possibly greater than that of the upper interface of the mantle transform zone. In the western Qinghai-Tibet Plateau, the Indian lithospheric plate is gently northward subducted and may have arrived to the south of Tarim plate. Due to the resistance from the gently northward subduction of the Indian mantle lithosphere in the western Qinghai-Tibet Plateau, the upwelling mantle material be-neath the Qiangtang block moves mostly toward the east to bring about the lateral eastward flow of the deep mantle hot material in the central Qinghai-Tibet Plateau.

关键词： travel-time residual receiver function lithosphere structure delamination Qiangtang block Bangong-Nujiang Suture

Crust and uppermost mantle structure of the Ailaoshan-Red River fault from receiver function analysis

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Science China Earth Sciences 2006年第10期49卷 1043-1052页

作者： XU Mingjie1, WANG Liangshu1, LIU Jianhua2, ZHONG Kai1, LI Hua1, HU Dezhao1 & XU Zhen1 1. Department of Earth Sciences, Nanjing University, Nanjing 210093, China 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 1. Department of Earth Sciences Nanjing University Nanjing 210093 China 2. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

S-wave velocity structure beneath the Ailaoshan-Red River fault was obtained from receiver functions by using teleseismic body wave records of broadband digital seismic stations. The average crustal thickness, Vp/Vs ratio and Poisson’s ratio were also estimated. The results indicate that the interface of crust and mantle beneath the Ailaoshan-Red River fault is not a sharp velocity discontinuity but a characteristic transition zone. The velocity increases relatively fast at the depth of Moho and then increases slowly in the uppermost mantle. The average crustal thickness across the fault is 36―37 km on the southwest side and 40―42 km on the northeast side, indicating that the fault cuts the crust. The relatively high Poisson’s ratio (0.26―0.28) of the crust implies a high content of mafic materials in the lower crust. Moreover, the lower crust with low velocity could be an ideal position for decoupling between the crust and upper mantle.

关键词： receiver function, Ailaoshan-Red River fault, velocity structure, Poisson's ratio, crust and upper mantle.

Determining endemic values of cutaneous leishmaniasis in Iranian Fars province by retrospectively detected clusters and receiver operating characteristic curve analysis

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Asian Pacific Journal of Tropical Biomedicine 2019年第9期9卷 359-364页

作者： Marjan Zare Abbas Rezaianzadeh Hamidreza Tabatabaee Hossain Faramarzi Mohsen Aliakbarpour Mostafa Ebrahimi Department of Epidemiology School of HealthShiraz University of Medical SciencesShirazIran Colorectal Research Center Shiraz University of Medical ScienceShirazIran Research Center for Health Sciences Shiraz University of Medical SciencesShirazIran Department of Community Medicine Medical SchoolShiraz University of Medical SciencesShirazIran Department of Communicable Diseases Shiraz University of Medical ScienceShirazIran

Objective: To determine the endemic values of cutaneous leishmaniasis in different cities of Fars province, Iran. Methods: Totally, 29 201 cases registered from 2010 to 2015 in Iranian Fars province were selected, and the endemic values of cutaneous leishmaniasis were determined by retrospective clusters derived from spatiotemporal permutation modeling on a time-series design. The accuracy of the values was assessed using receiver operating characteristic(ROC) curve. SPSS version 22, Arc GIS, and ITSM 2002 software tools were used for analysis. Results: Nine statistically significant retrospective clusters(P<0.05) resulted in finding seven significant and accurate endemic values(P<0.1). These valid endemic scores were generalized to the other 18 cities based on 6 different climates in the province. Conclusions: Retrospectively detected clusters with the help of ROC curve analysis could help determine cutaneous leishmaniasis endemic values which are essential for future prediction and prevention policies in the area.

关键词： Cutaneous leishmaniasis Retrospective clusters receiver operating characteristic curve Endemic values Fars province

Research on a Velocity Determination and FDE Algorithm for High-Dynamic GNSS receiver

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China Communications 2015年第S2期12卷 64-71页

作者： QI Jianzhong SONG Peng School of Computer and Communication Engineering University of Science and Technology Beijing North China University of Technology

A velocity determination algorithm of GNSS receiver for high speed and high acceleration carrier in motion is mainly discussed in this paper. For this algorithm, the Doppler frequency value is extracted from the satellite carrier tracking loop, and(α, β, γ) filter is adopted for smoothing, and least square is adopted to calculate the receiver speed and local clock drift. To get accurate determination value, a kind of fault detection and exclusion technology(FDE) is designed in this paper; the satellite Doppler frequency value with large error is detected and exclusion. Finally, the signal of GNSS signal simulator and actual navigational satellite signal are received for test, getting good velocity determination result.

关键词： GNSS receiver α-β-γ filter velocity determination FDE technology

A Direct Conversion WLAN receiver

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A Direct Conversion WLAN Receiver

Numerical investigation of thermal performance of heat loss of parabolic trough receiver

2005 6th International Conference on ASIC

作者： Jingguang Wang Jinju Wang Yumei Huang Weilun Shen Xiaofeng Yi Zhiliang Hong State Key Lab of ASIC and System Fudan University

ISBN: (纸本)0780392108

＜正＞A direct conversion receiver for WLAN 802.11b is presented in 0.18μm CMOS *** contains a complete receiver chain with low noise amplifier,I/Q mixer,programmable gain amplifier and base band filter.A 4.8GHz divider is used to generate 2.4GHz quadrature clock for I/Q *** reception path is dc coupled and a feed back low pass filter is added to reduce the dc-offset and 1/f *** noise figure of receiver is 5.2dB,the UP3 is -l4.5dBm at high gain *** the supply voltage of 1.8V,the over all power consummation is about 100mW. The chip area with pads is 2.6mm×2.5mm.

关键词： CMOS direct conversion receiver WLAN low noise amplifier mixer programmable gain amplifier base band filter dc-offset 1/f noise.

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Science China(Technological Sciences) 2010年第3期53卷 444-452页

作者： Modibo Kane TRAORE Key Laboratory of Enhanced Heat Transfer and Energy Conservation Ministry of Education and Key Laboratory of Heat Transfer and Energy Conversion Beijing Municipality College of Environmental and Energy Engineering Beijing University of Technology

Based on the analysis of computation methods and heat transfer processes of the parabolic trough receiver running in steady state, a two-dimensional empirical model was developed to investigate the thermal performance of heat loss of parabolic trough receivers under steady state equilibrium. A numerical simulation was conducted for the parabolic trough receiver involved in a literature. Comparisons between numerical and experimental results show that the empirical model is accurate enough and can be used to investigate the thermal performance of heat loss of parabolic trough receivers. The thermal performance of heat loss of UVAC3 and the new-generation UVAC2008 was investigated respectively. The simulation results show that selective coatings and annular pressure influence the thermal performance of heat loss of parabolic trough receivers greatly, wind velocity influences the thermal performance of thermal loss of parabolic trough receivers only a little in contrast with the emittance of selective coatings and air pressure in annular space. And the thermal performance of thermal loss of the new-generation parabolic trough receiver has been improved in a large amount.

关键词： parabolic trough receiver two-dimensional empirical model thermal performance of heat loss annular space selective coating wind velocity

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Structural optimization design on the arc receiver array of forward-looking sonar

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Chinese Journal of Acoustics 2023年第1期42卷 40-57页

作者： ZHAO Dongdong LI Fuzeng CHEN Peng MAO Weibo GUO Xinxin College of Computer Science and Technology Zhejiang University of TechnologyHangzhou 310023 College of Information Engineering Zhejiang University of TechnologyHangzhou 310023 Institute of Deep-sea Science and Engineering Chinese Academy of SciencesSanya 572000

Aiming at the problems that poor isotropic of linear array and limited effective aperture of semicircular array in forward-looking sonar,an optimized structural design method of arc receiving array is *** to different extent of imaging sector,the central angle of arc receiving array is designed to make all elements participate in beamforming of all *** far and near-field focusing model of arc receiving array is established,and the directivity function of arc receiving array is *** radius of arc receiving array with the best beam performance is calculated according to the threshold condition of the boundary beam grating *** comparison of the beam performance at different sector extent of arc array,linear array and semicircular array shows that,the main lobe performance of the arc receiving array is improved by 8%with the view extent between 90°to 130°,and the grating lobe level of the boundary beam is optimized by 4%.The comparison of simulation images with the view extent of 120°and depth of 100 m shows that the cross-directional resolution depth is increased by 20 m and 45 m compared with linear array and semicircular array,the parameter storage capacity is only 2.7%of the linear *** arc array has the advantages of large effective aperture and isotropic beam,which can effectively improve the detection performance of forward-looking sonar system and reduce difficulty of algorithm implementation.

关键词： receiver beam optimization

Geometric optimization model for the solar cavity receiver with helical pipe at different solar radiation

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Frontiers in Energy 2019年第2期13卷 284-295页

作者： Chongzhe ZOU Huayi FENG Yanping ZHANG Quentin FALCOZ Cheng ZHANG Wei GAO School of Energy and Power Engineering Huazhong University of Science and TechnologyWuhan 430074China China-EU Institute for Clean and Renewable Energy Huazhong University of Science and TechnologyWuhan 430074China School of Energy and Power Engineering China-EU Institute for Clean and Renewable EnergyHuazhong University of Science and TechnologyWuhan 430074China PROMES-CNRS Laboratory 7 rue du Four Solaire66120 Font-Romeu-Odeillo-viaFrance

In consideration of geometric parameters, several researches have already optimized the thermal efficiency of the cylindrical cavity receiver. However, most of the optimal results have been achieved at a fixed solar radiation. At different direct normal irradiance (DNI), any single optimal result may not be suitable enough for different regions over the world. This study constructed a 3-D numerical model of cylindrical cavity receiver with DNI variation. In the model of a cylindrical cavity receiver containing a helical pipe, the heat losses of the cavity and heat transfer of working medium were also taken into account. The simulation results show that for a particular DNI in the range of 400 W/m2 to 800 W/m2, there exists a best design for achieving a highest thermal efficiency of the cavity receiver. Besides, for a receiver in constant geometric parameters, the total heat losses increases dramatically with the DNI increasing in that range, as well as the temperature of the working medium. The thermal efficiency presented a different variation tendency with the heat losses, which is 2.45% as a minimum decline. In summary, this paper proposed an optimization method in the form of a bunch of fitting curves which could be applied to receiver design in different DNI regions, with comparatively appropriate thermal performances.

关键词： cylindrical cavity receiver 3-D numerical simulation geometric optimization direct normal irradia-tion

Four-dimensional direct detection receiver enabling Jones-space field recovery with phase and polarization diversity

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Photonics Research 2024年第3期12卷 399-410页

作者： QI WU YIXIAO ZHU XUEYANG LI HEXUN JIANG CHEN CHENG MENGFAN FU YIKUN ZHANG QUNBI ZHUGE ZHAOHUI LI WEISHENG HU Peng Cheng Laboratory Shenzhen 518055China State Key Laboratory of Advanced Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Electronics and Information Technology and Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems Sun Yat-sen UniversityGuangzhou 510006China

Data centers,the engines of the global Internet,rely on powerful high-speed optical *** optical fiber communication,classic direct detection captures only the intensity of the optical field,while the coherent detection counterpart utilizes both phase and polarization diversities at the expense of requiring a narrow-linewidth and high-stability local oscillator(LO).Herein,we propose and demonstrate a four-dimensional Jones-space optical field recovery(4-D JSFR)scheme without an *** polarization-diverse full-field receiver structure captures information encoded in the intensity and phase of both polarizations,which can be subsequently extracted *** our knowledge,our proposed receiver achieves the highest electrical spectral efficiency among existing direct detection systems and potentially provides similar electrical spectral efficiency as standard intradyne coherent detection *** fully recovered optical field extends the transmission distance beyond the limitations imposed by fiber chromatic ***,the LO-free advantage makes 4-D JSFR suitable for photonic integration,offering a spectrally efficient and cost-effective solution for massively parallel data center *** results may contribute to the ongoing developments in the theory of optical field recovery and the potential design considerations for future high-speed optical transceivers.

关键词： polarization receiver phase

Research and practice of varied GPS receiver working together

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中国有色金属学会会刊：英文版 2005年第S1期15卷 200-203页

作者： JI Chang-dong, QIAO Yang-wen, XIA Chun-lin (Liaoning Technical University, Fuxin 123000, China)

The GPS receiver working together was researched and practiced deeply, which mainly included the choice of scheme how to lay the network and the development of software use during the data processing. The software exa... 详细信息

关键词： Ashtech receiver Trimble receiver integration of operation RINEX